This invention relates to a cue signal-recording apparatus for recording a cue signal which is used, for example, in a dictation-recording tape recorder to detect the start point of particular recorded data.
A cue signal is often applied in a dictation-recording tape recorder. The cue signal is recorded on a tape immediately before the start point of dictated data, and then said dictated data is recorded on the tape. When typing an expression from the recorded dictation, a typist can quickly detect the start point of a particular recorded dictation which is to be typed by utilizing the cue signal.
A cue signal for detecting the start point of a particular recorded data is generally sent forth from an astable multivibrator. The frequency of such type of vibrator is liable to vary with changes with time and temperature in the impedance of the CR parts used and also with changes in the voltage of a power source. Now let it be assumed that a circuit for detecting a cue signal when a tape is set at a reproduction mode is of the type which carries out the frequency separation of the cue signal. In such a case, when the frequency of a cue signal oscillator varies widely with the aforementioned changes of time and temperature in the impedance of the CR parts, then the frequency separation of the cue signal will sometimes be disabled. Further, when the cue signal is detected by frequency separation, then a cue signal oscillator must have its frequency adjusted to a prescribed value for each tape recorder. This requirement constitutes one of the drawbacks of presenting difficulties in the reduction of the manufacturing cost of a tape recorder having a cuing function.